Barley is a very important grain in the world today. It is very versatile in every way. It has been well adapted through its evolution. It has a very mysterious and much debated beginning. Now however, barely has become well known and so have its many uses. Barley, which is of the genus Hordeum, is a cereal that belongs to the grass family Poaceae. Barley has many different varieties. The most common is Hordeum vulgare, which is a six-rowed type of barley that has a spike notched on opposite sides with three spikelets on each notch. At each notch there is a flower or floret that later develops into a kernel. Hordeum distichum is a two-rowed type of barley that has central florets producing kernels and it has lateral florets that are sterile. Lastly there is Hordeum irregulare which has fertile central florets and different arrangements of sterile and fertile lateral florets.